Gold(I) Complexes of P,N Ligands and Their Catalytic Activity

Gold(I) complexes were readily prepared by reaction of the respective ligands with (Me 2 S)AuCl in CH 2 Cl 2 . Complexes of formula LAuCl {L = diphenyl(2‐pyridyl)phosphane (PPh 2 Py), ( R )‐(+)‐4‐[(2)‐(diphenylphosphanyl)‐1‐naphthyl]‐ N ‐[( R )‐1‐phenylethyl]‐1‐phthalazinamine (PINAP)} were obtained when a 1:1 molar ratio of ligand to starting gold precursor was used. When a 2:1 ratio of ligand to gold precursor was used with PPh 2 Py or MandyPhos as ligands, complexes of the type L 2 AuCl were obtained. All complexes were fully characterized, and single‐crystal X‐ray structures could be determined for four complexes. Chloride ions were removed by reaction with silver salts, such as AgNTf 2 , AgOTf and AgBF 4 , for the use of these complexes as catalysts. After the catalytic reaction with alkynes and alcohols in acetonitrile, a unique trinuclear gold(I) complex derived from [(PPh 2 Py)Au]BF 4 could be characterized by X‐ray structural analysis, showing a mode of catalyst deactivation.